1. Field of the Invention
The present invention relates to novel Geldanamycin derivatives and antitumor drug containing the same as an active ingredient.
2. Description of the Prior Arts
Geldanamycin is the antiprotozoan antibiotic produced by streptomyces hygroscopicus var. geldanus var. nova strain (Journal of Antibiotics Vol. 23, Page 442 (1970)) and has the following formula ##STR3## (Journal of the American Chemical Society Vol. 92, Page 7591 (1970)).